1. Solène Turquety – ADOMOCA, 14 Novembre 2006 Intercomparaison du CO mesuré par MOPITT en visée au nadir et par ACE en occultation solaire: complémentarités pour l’étude du transport de la pollution Solène Turquety, Cathy Clerbaux, Kathy Law, Juliette Hadji-Lazaro Service d'Aéronomie, IPSL, Paris, France. Pierre-François Coheur, Daniel Hurtmans, Catherine Wespes, Ariane Razavi, Service de Chimie Quantique et Photophysique, Université Libre de Bruxelles. Didier Hauglustaine, Anne Cozic, Laboratoire des Sciences du Climat et de l’Environnement, IPSL, Gif-sur-Yvette, France Christopher D. Boone, Peter F. Bernath Department of Chemistry, University of Waterloo, Waterloo, Canada

2. Solène Turquety – ADOMOCA, 14 Novembre 2006 IPCC : CO emissions × 3 for East Asia and India between 2000 and 2100 (scenario A2p) NOx emissions × 4 → Long-range transport has important implication for air quality in downwind regions → Reaches a maximum in spring due to active anticyclone and strong westerly winds → Transport mainly in the middle troposphere → Trans-Pacific transport of pollution in 5-10 days Richter et al., Nature, 2005 2001 Heald et al., JGR, 2006 East central China Hong Kong X 10 6 MOPITT Clerbaux et al., 2006 Importance of the long-range transport of pollution from Asia Is there information on Asian pollution in the ACE solar occultation measurements in the middle and upper troposphere?

3. Solène Turquety – ADOMOCA, 14 Novembre 2006 [Clerbaux et al., GRL, 2005] ACE – Atmospheric Chemistry Experiment ACE-SCISAT-1 is a Canadian mission launched on August 13th, 2003 Primary instrument : ACE-FTS, high resolution IR spectrometer Solar occultation : measurement of atmospheric profiles of temperature, pressure and a series of trace gases during sunrise and sunset Modified global fit (Levenberg-Marquardt) [Boone et al., 2005] Retrieval of key species for tropospheric studies: O3, H2O, H2O2, CO, CH4, C2H6, C2H2, HCN, CH3Cl, SF6, OCS, HNO3, PAN,… Vertical resolution ~4km in the middle and upper troposphere http://www.ace.uwaterloo.ca/mission.htm

4. Solène Turquety – ADOMOCA, 14 Novembre 2006 Exploiting the complementarities for the study of long range transport Focus on March-April 2005, a time period with ACE observations at mid-latitudes 1.Intercomparison of CO observations : MOZAIC (in situ), MOPITT (nadir), ACE (solar occultation) 2.Study transport event in March-April 2005 with the global model LMDz-INCA ACE occultations March–April–May 2005 ( + ) w/ ATSR hotspots (.) CO @ 500 hPa (ppbv) 40 100160 MOPITT @ 500hPa – April 2005

5. Solène Turquety – ADOMOCA, 14 Novembre 2006 ACE solar occultation measurements vs. MOZAIC in situ data Comparisons for March-April-May 2004: +/- 2.5°, +/- 1 day MOZAIC + ACE @ 12km (April, 2005) 20050405 (26°N, 54°E) ACE MOZAIC 500 20050504 (46°N, 72°W) ACE MOZAIC 200 20050506 (48°N, 15°E) 250 ACE MOZAIC

6. Solène Turquety – ADOMOCA, 14 Novembre 2006 Intercomparison of remote sensing CO measurements Rodgers and Connor, 2003: Apply retrieval characteristics of lower resolution measurement (e.g. MOPITT) to higher resolution measurement (e.g. in situ data, model simulations) Intercomparison of Level 2 retrievals from different instruments: Need to account for characteristics of the retrievals. ACE CO retrieval Averaging Kernels [Clerbaux et al., 2005] High vertical resolution ~ 4 km MOPITT CO retrieval Averaging kernels Low vertical resolution ~ 7 km Smoothed profile using low resolution measurement characteristics Low resolution a priori profile Low resolution Averaging kernels High resolution: original retrieval

7. Solène Turquety – ADOMOCA, 14 Novembre 2006 MOPITT nadir vs. ACE occultation measurements MOPITT – April 4, 2005 * ACE occultations - - ss8848.asc Intercomparison +/- 1°, same day MOPITT MOPITT a priori profile ACE high resolution ACE/MOPITT (smoothed) Good agreement : Δ ≤ 18% MOPITT tends to give larger mixing ratios in the upper troposphere ACE observations allows complementary measurement of plume vertical structure

8. Solène Turquety – ADOMOCA, 14 Novembre 2006 DOFs=0.7 Intercomparison +/- 1°, same day MOPITT MOPITT a priori profile ACE high resolution ACE/MOPITT (smoothed) MOZAIC high resolution MOZAIC/MOPITT (smoothed) ACE+MOZAIC/MOPITT (smoothed) DOFs ~ 2: information haute troposphère dans MOPITT DOFs ~ 1: biais ACE / MOPITT dans la haute troposphère, liée à la contribution de la basse troposphère dans MOPITT

9. Solène Turquety – ADOMOCA, 14 Novembre 2006 LMDz-INCA global model simulation Global GCM LMDz (Laboratoire de meteorologie Dynamique, zoom), version 4 (http://www.lmd.jussieu.fr/~lmdz) Chemistry module INCA (Interaction of Chemistry and Aerosols) NMHC version 2: 85 chemical species; over 300 reactions (Hauglustaine et al., 2005, http://www-lsceinca.cea.fr/) Simulation using the nudged version, driven by ECMWF meteorological fields Resolution 3.75° longitude x 2.5° latitude, 19 vertical levels (surface – 3hPa) Anthropogenic emissions from EDGAR v.2; biogenic emissions from GEIA Biomass burning emissions (1st approximation) : Climatology (average 1995-2003 from Van der Werf et al.) redistributed according to MODIS fire detection for 2005 (monthly emissions) INCA x MOPITT AK MOPITT CO @ 700hPa – April 2005SCIAMACHY tropospheric NO2 (KNMI) – April 2005 INCA tropospheric NO2 Underestimate anthropogenic emissions (Asia) ; Need more accurate biomass burning

10. Solène Turquety – ADOMOCA, 14 Novembre 2006 Long-range transport from Asia in March-April 2005 INCA x MOPITT AK MOPITT @ 500hPa – 20050327-20050404 2005032920050330 20050331 20050401 2005040220050403 ACE observations ECMWF winds

11. Solène Turquety – ADOMOCA, 14 Novembre 2006 Comparison of CO from ACE and the LMDz-INCA model INCA @ 400 hPa 20050327-20050404 Average INCA distribution for the days of ACE comparisons

12. Solène Turquety – ADOMOCA, 14 Novembre 2006 120° 150° 180°-150°-120° 120° 150° 180°-150°-120° ACE occultation tropopause Comparison of CO from ACE and the LMDz-INCA model

13. Solène Turquety – ADOMOCA, 14 Novembre 2006 120° 150° 180°-150°-120° 120° 150° 180°-150°-120° ACE occultation Comparison of CO from ACE and the LMDz-INCA model

14. Solène Turquety – ADOMOCA, 14 Novembre 2006 INCA @ 400 hPa 20050327-20050404 Average INCA distribution for the days of ACE comparisons Comparison of O3 from ACE and the LMDz-INCA model

15. Solène Turquety – ADOMOCA, 14 Novembre 2006 120° 150° 180°-150°-120° ACE occultation 120° 150° 180°-150°-120° Comparison of O3 from ACE and the LMDz-INCA model

16. Solène Turquety – ADOMOCA, 14 Novembre 2006 120° 150° 180°-150°-120° ACE occultation Stratospheric intrusion? O3 net production Fraction of stratospheric O3 CO NOx

17. Solène Turquety – ADOMOCA, 14 Novembre 2006 ACE occultation 120° 150° 180°-150°-120° Stratospheric intrusion? O3 net production Fraction of stratospheric O3 CO NOx

18. Solène Turquety – ADOMOCA, 14 Novembre 2006 Conclusions Future work Comparisons to TES/Aura observations Improve emissions in the LMDz-INCA simulation using results from inverse modeling analyses Analysis of ozone production during the long range transport Assimilation: complementary constraint from different observation geometry? Vertical resolution vs. number of observations intergrated? ACE occultation measurements provide information on a series of trace gases with good vertical resolution in the upper troposphere CO measurements consistent with MOZAIC in situ and MOPITT satellite measurements Combined analysis with nadir measurements (better spatio-temporal resolution, lower vertical resolution) and global model provides information on the global context and transport pathways ACE gives detailed information on the chemical composition of air masses in the upper troposphere Interesting tool for the study of the long range transport